Birthdays calendar behavior

Hello RobertSparnaaij,

thank you for your reply; you confirmed my doubts.

Experiment

I made this experiment/test (just to increase my knowledge).

The objective was to set the Reminder to 0 days (default is 18 hours) for all recurring appointments/events inside Birthdays' calendar, in bulk.

I achieved the objective by using https://developer.microsoft.com/en-us/microsoft-365/blogs/microsoft-graph-powershell-preview-now-on-powershell-gallery/. This is the piece of PowerShell code:

# You'll be asked to sign in via web browser:
Connect-Graph -Scopes "Calendars.ReadWrite","User.Read.All" 
$userId = (Get-MgUser | Where-Object {$_.DisplayName -eq "Bill Gates"}).Id

# If the 'Top' parameter is missing, it returns one calendar only (the default user's calendar):
$calendarId = (Get-MgUserCalendar -UserId $userId -Top 10 | Where-Object {$_.Name -eq "Birthdays"}).Id

# If the 'Top' parameter is missing, it returns 10 events only (maybe it's the default:
Get-MgUserCalendarEvent -CalendarId $calendarId -UserId $userId -Top 2000 | %{ Update-MgUserEvent -EventId $_.Id -UserId $userId -ReminderMinutesBeforeStart 0}

Even if the Update-MgUserEvent cmdlet returns the error below (for each item in loop), Reminder was changed successfully. Of course, the error itself can be suppressed by adding the parameter -ErrorAction SilentlyContinue.

Update-MgUserEvent : The server responded with an unrecognized response, Status: OK
At line:1 char:80
+ ... p 1000 | %{ Update-MgUserEvent -EventId $_.Id -UserId $userId -Remind ...
+                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : InvalidOperation: ({ UserId = 0a24...oftGraphEvent }:<>f__AnonymousType41`3) [Update-MgUserEvent_UpdateExpanded], RestException`1
    + FullyQualifiedErrorId : OK,Microsoft.Graph.PowerShell.Cmdlets.UpdateMgUserEvent_UpdateExpanded

Bye,

Luca